Liquid pumping and circulating system



April 10, 1934. c. sToKEs 1,954,461

LIQUID PUMPING AND CIRCULATING' SYSTEM Filed Nov. 10, 1924 2 INVENTOR.

A TTORNEYS.

Patented Apr. 10, 1934 UNITED STATES LIQUID PUMPING AND CIRCULATINGSYSTEM Charles Lawrence Stokes, Los Angeles, Calif.

Application November 10, 1924, Serial No. 748,932

8 Claims.

My invention relates to improvements in liquid circulating and pumpingsystems wherein the waste heat of an internal combustion engine isutilized for circulating or transferring a liquid.

The principal object of my invention is to provide a closed circulatorysystem wherein a fluid is repeatedly vaporized and condensed, thevapor-' izing being done by the waste heat in the fuel supply to aninternal combustion engine, and the condensing being done by the fuelbeing supplied to the same engine.

A further object of my invention is to provide a vaporizing chamber foran internal combustion engine wherein steam, or superheated steam, is

continually circulated and condensed by the transfer of its latent heatto a volatile fuel in indirect contact with the steam in the vaporizingchamber.

A further object of my invention is to provide a reciprocating condenserwhich acts as a pump and a condenser.

A further object of my invention is to provide a simple liquid pumphaving a minimum number of working parts.

Referring to the drawing, in which the same numbers indicate likeparts:-

Fig. 1 is a view of an engine showing my invention in operative relationthereto.

Fig. 2 is a vertical section of the vaporizing chamber shown in Fig. 1.

Fig. 3 is a transverse section along the lines 33 of Fig. 2.

Fig. 4 is a diagram showing my invention applied to pumping systems forinternal combustion engines.

Fig. 5 is a vertical section in part view of part of Fig. 4.

Fig. 6 is an alternative construction of Fig. 5.

Fig. 7 is an alternative construction of Fig. 5

It is considered highly desirable in modern gas engine practice toprovide some method of vaporizing the gasoline being supplied to theengine and in general the methods provided include the use of the wasteheat in the engine exhaust gases which is generally supplied to asocalled hot spot, the exhaust gases being often diverted from the mainexhaust pipe to the hot spot. Any diversion of gases through conduitsinvariably causes condensation therein of carbon and lubrieating oilvapors whereby such conduits become choked in a comparatively short timeand cannot function as desired. A hot air pipe is also provided as arule which has the defect of raising the temperature of the air suppliedto the engine as well as partly vaporizing the fuel.

These defects I am now enabled to overcome by providing a steamcirculatory system through a hot spot wherein the latent heat in thesteam is transferred principally to the volatile fuel being supplied tothe engine and the steam thereby condensed is circulated, reheated andcondensed in cyclic fashion.

In Fig. 1 an internal combustion engine 1 is rovided with an exhaustpipe 2, an inlet manifold 3 and a carburetor 4. Between the carburetor 4and the intake manifold 3 is placed a steam vaporizing hot spot 5 whichis joined at its upper end by a pipe 6 to the upper end of a steamchamber '7, the lower end of '7 being joined by a pipe 8 to the lowerend of 5.

The carburetor d is supplied with air through a port 9 and with liquidfuel through a pipe 10, the discharge of air and liquid fuel from 4being controlled by a throttle 11. The position of throttle 11 whenclosed will govern the discharge of an idling mixture of liquid fuel andair supplied through a pipe 12.

Referring to Figs. 2 and 3 it will be seen that the manifold 3 isexpanded slightly at its base to be joined by the flanged upper end of 5which consists of a tubular chamber through which is passed a pluralityof thin walled metal tubes 13, the combined areas of which preferablyslightly exceed the area of discharge of the inlet manifold 3 orcarburetor 4.

The tubes 13 therefore provide a passage for air and liquid fuel throughtheir interiors from 4 to 3 and exteriorly the tubes 13 are subjected tothe heat supplied by the vaporization of water in '7 passing throughpipe 6 to the upper end of 5. The steam condensing in 5 is withdrawn atits lower end, which is preferably slanted as shown, through the pipe 8which reconveys the condensed Water to the lower end of 7.

The chamber 7 is encased, or subjected to the heat of the exhaust gases,in the exhaust pipe 2 and contains a predetermined quantity of a liquidsuch as distilled water, methyl alcohol, ethyl alcohol, or many otherliquids are suitable for my purposes. In general however I prefer to usedistilled water in 7 because the characteristics of the same whensubject to heat do not vary the world over.

A port 14 is provided in the upper end of 5, being tightly closednormally by a plug 15 to the end that the system comprising 5, 6, '7,and 8 will constitute a closed circulatory system.

The operation of the system described is that upon cranking the engine1, the throttle 11 will be very slightly open in the direction of thearrow shown in Fig. 2 whereupon the engine induction vacuum will causean idling mixture of air and liquid fuel from 12 to be drawn upwardlyand through the tubes 13 closest to the wall through which fuel and airis supplied and also closest to the wall to which 6 is joined.

If it be assumed that in extremely cold weather and any water in 7 isfrozen, the quantity of water therein is in general so small that thefirst few explosions of the engine conveys sufiicient heat through 2 tomelt the same and rapidly convert the same to steam. The steam thenpasses through the pipe 6, which may be relatively large when Comparedto 8 and is suitably insulated against heat losses, to the interior of 5where it impinges against the tubes 13 through which the idling mixturefrom 12 is passing thereby heating the same and transferring its heatthrough the thin metal walls of tubes 13 to the film of liquid fuelbeing drawn along the interior walls of 13 and the transfer of said heatcauses the condensation of the steam to water which then falls to thebottom of 5 and is retransferred through 8 to the interior of the bottomof 7 where it is revaporized and again passes through the system.

.It should be understood of course that the circulation of steam andrecirculation of condensed water through the system described iscontinuous as long as the engine 1 is operated so that, inasmuch as ahigher heat is conveyed to '7 through the pipe 2 at higher enginespeeds, the circulation of steam continues at a higher rate according asthe throttle 11 is more fully open. Thus,

automatically, the application of heat by the steam to the tubes 13 isprovided in increasing quantity according to the increased demands ofthe engine 1.

In order to provide maximum efiiciency for the circulatory systemwhereby the water in '7 will be quickly vaporized with a minimumapplication of heat thereto, the pipe 6 made in coil form as shown inFig. 5 and part of the same may be placed in the interior of 2, wherebythe steam generated in '7 is superheated prior to its entry into 5.Another feature for providing the same maximum efiiciency is thatprimarily upon starting the system, the plug 15 is removed and thesystem is brought to a sufiicient temperature to fill the same withsteam thereby expelling all air and other gases contained therein. Assoon as steam issues from 14, the plug 15 is reinserted for preventingthe ingress of air to the interior of 5. Thus after the system is cooleddown, a predetermined partial vacuum will prevail therein to the endthat the water, or other liquid, in 7 will boil at a predetermined lowtemperature, lower than normal.

The temperature of exhaust gases as a rule varies from 400 F. to about1490" F. and thus it will be seen that ample temperature conditions areprovded for ensuring the operation of this system under all conditions,more particularly if it is preferred to operate the system initiallyunder vacuum as descrbed.

A similar circulatory system is provided as illustrated in Fig. 4wherein the carburetor 4 is provided with liquid fuel through the pipe10 from a liquid fuel reservoir 16 placed at a lower level than 4. Inthis case a pump chamber 17 is connected at its upper end to the pipe 10and a pipe 18 serves to convey liquid fuel from 16 through the upper endof 17 to the interior of a reciprocating metal bellows, or expansiblemember 19 which member is securely held to the cover 20 enclosing theupper end of 1'? and the pipe 18 extends through 20 to the lower portionof the interior of 19 for a purpose to be herinafter described.

A check valve 21 is placed in 18 for permitting the passage of liquidfuel solely from 16 to the interior of 19 and a check valve 22 is placedin 10 for permitting the passage of liquid fuel solely from 19 to 4 anda by-pass pipe 22a connects 10 with the pipe 18 on the side of 21nearest the reservoir 16. A regulating check valve 23 is placed in 220.in order to maintain a predetermined discharge pressure of liquid fuelpassing from the interior of 19 through 10 to the carburetor 4, andcheck valve 23 is arranged to permit any liquid fuel due to excessivepressure to be by-passed from 10 to 18.

A priming plug 23a is provided for filling the interior of 19 atstarting with liquid fuel, the lower end of 19 being securely closed bya tapered plug 24 arranged to seat in the lower end 25 of 17 which isalso tapered and provided with a boss 26. 24 is centrally drilled at 27to slidably receive the pipe 8, a small annular space being providedtherebetween and the passage 2'? communicates through a plurality ofpassages 28 to the interior of 1'7. A plug 15 is provided for the samepurpose of placing the system under vacuum as already described.

Referring particularly to Figs. 4 and 5, if it be assumed that thesystem is cold, the appara-' tus will be in position illustrated in Fig.5 wherein 24 will be seated in 25, the bellows 19 being expanded due tothe vacuum in the system, the interior of 19 being filled with liquidfuel. A predetermined quantity of water is contained in '2, whichquantity of water is such as not to fill 25 beyond the upper level ofthe pipe 8 when 19 is fully compressed.

Upon starting the engine, the heat of the ex haust gases in 2 istransferred to the water in 7 thereby increasing the pressure on theabsolute scale in 17 thereby causing 19 to first of all assume a normalposition and thereafter to be compressed thus forcing liquid fuel fromthe interior of 19 through 10 to the carburetor 4, any excess fuel beingby-passed through 22a and 23 to 18. The pressure caused by the steampassing from 7 through 6 to the interior of 17 will gradually reach amaximum whereby 19 will reach a maximum compression but this maximumpressure of steam is then rapidly reduced due to the condensationeffects of the cool walls of 19 whereupon the condensed water willcollect in the lower end of 25 and the bellows 19 will then start toexpand thus drawing in a fresh supply of liquid fuel from 16 through 18and 21 and said supply of fresh liquid fuel, being cool, is directedfrom the pipe 18 to the lower end of the interior of 19 for circulatingthe cool liquid through the bellows and impinging the same upon theinterior side of 24, it being understood that during the expansion of19, the check valves 22 and 23 will be closed while the check valve 21will be open.

The expansion of 19 will thus cause the condensed water in the lowerpart of 25 to be forced upwardly therein away from the pipe 8 until thesame enters the passages 28 and the water is thus admitted to theinterior of 8 in a substantially good quantity to the end that saidquantity will reach the chamber 7 without being converted to steam, butupon reaching 7, the same is flashed into steam due to the heat of 7 andthe cycle is then repeated.

It should be understood that while the steam is pref rably superheatedfor application to the systems described with reference to Figs. 1, 2and 3. It is not necessary to superheat said steam when used inconnection with the system cescribed for Figs. 4, 5, 6 and 7, but thesame may be superheated depending upon the length of pipe 10 in order tomaintain the water in the form of steam for a comparatively long travel.In

the pumping system just described in Figs. 4 and 5 it will be imderstoodthat the circulatory system is intermittent in order to obtain thedesired reciprocating action for 19 and therefore the water originallysupplied to 7 will be of a definnite predetermined quantity so thatafter one vaporization thereof, the condensed water will be able to beheld in 25 without discharge therefrom until injected into 7 through 8by the expansion of 19.

Referring to Fig. 6 a similar intermittent pumping action as describedtakes place the essential difference in construction being that the pipe8 is arranged to directly enter the upper end of 7 and the pipe 10 maybe eliminated. Also, the tapered plug 24 is solid being arranged to seatin 25 and inject water through an orifice 29 in the boss 26. In thismanner it will be seen that upon vaporizing the water in 7, the steamwill pass through 8 and 29 to cause a compression of 19 and the waterthereafter condensed in 17 will be maintained therein until a maximumsteam pressure is reached and thereafter the condensed water will beejected as a stream through the orifice 29 directly into 7, the pipe 8being of comparatively large diameter. The construction shown in Fig. 6is practically that of a reflux condenser wherein the reflux isrestrained from revaporization until a predetermined period has passedfor giving intermittent reciprocatory action to 19.

Referring to Fig. 7 a similar intermittent action is obtained by makingplug 24 as a disc and attaching thereto a valve 30 for closing theorifice 29, 30 being connected to 24 on a swivelled joint 31 by means ofa stem 32 containing an upper stop 33 and a lower stop 34. Between thestops 33 and 34 is held a spring 35 which is pivoted at each end on 17and is preferably in part corrugated for the purpose of providing a kickaction to the valve 30 at predetermined positions of 19, whereby asimilar action as already described takes place, it being understoodthat the pipe 8 in the present case also extends directly into the upperend of 7 and is of comparatively large diameter.

The action of the kick spring 35 is well understood and many equivalentstherefore are available and adaptable for a similar purpose.

In case accentuated condensing effect is desired in 17, the same may bemade of aluminum having thereon a series of radiating fins 35a, whichfins may also if desired extend interiorly of 17.

It will be of course obvious that the circulating and pumping system isapplicable for pumping of any description such as gasoline, oil, orwater and may be applied to liquid pumping systems generally, and thatany suitable means may be employed for supplying heat necessary tooperate the device.

I claim:

1. The method of transferring heat from one part to another in a fluidcirculatory system for internal combustion engines being supplied withliquid fuel which consists in applying the engine heat to aself-contained circulatory system and vaporizing liquid therein, passingthe vaporized liquid along one path to a cooler part of the cngine andtransferring the latent heat of the liquid to the liquid fuel wherebythe vapors of the liquid are condensed, utilizing the expansive force ofsaid volatized liquid for causing a flow of liquid fuel in proximity tosaid volatized liquid, then returning the first-named liquid throughanother path for further vaporization, the vaporizing, circulating andcondensing being conducted at a lower temperature than that required toboil the liquid fuel at normal atmospheric pressure.

2. In combination, a casing comprising a receptacle for holding liquidfuel, an internal combustion engine, a fuel passage through said casing,a boiler, a pair of conduits connecting said casing to said boiler forforming a closed circuit, a fluid in said circuit, means forcontinuously heating said boiler for vaporizing said fluid, said fluidbeing condensed by coming in contact with the walls of said passageWithin said casing and being automatically returned to said boiler to berevapo-rized and means for discharging said fuel from said receptacle,said means being operated by the expansive force of the vaporized fluid.

3. In combination, an exhaust pipe, a boiler associated with said pipeand adapted to contain a fluid, a casing, a pump within said casing,passages leading into and out of said pump through which liquid fuel isadapted to pass, and a passage from said boiler to said casing forconveying a fluid from said boiler to said casing for heating saidliquid fuel and for operating said pump and a second passage forreturning said fluid to said boiler.

4. A method of heating liquid fuel for an in-- ternal combustion enginewhich consists in vaporizing a liquid, transferring the same along onepath into close proximity to said liquid fuel while the same is in apassive state for heating the same, utilizing the expansive force ofsaid liquid when vaporized for causing a flow of said fuel andcondensing said liquid, and returning the condensed liquid along anotherpath to be revaporized.

5. In combination, an internal combustion engine, a casing, pumpmechanism within said oasing, a vaporizer, means for conducting avaporized fluid to said casing through one conduit for operating saidmechanism, and means for automatically returning the condensed fluid tosaid vaporizer along another conduit.

6. In combination, an internal combustion engine, a carburetor therefor,means including a pump for supplying fuel to said carburetor, and aclosed fluid circulating system heated by the exhaust fro-m said enginefor operating said pump, said system comprising a plurality of conduitsfor conducting said fluid to and from said pump.

7. In combination, an internal combustion engine, a carburetor therefor,means including a pump for supplying fuel to said carburetor, and afluid circulating system heated by the exhaust from said engine foroperating said pump and for heating said fuel as the same passes throughsaid pump, said pump having separate intake and discharge conduits andsaid system having independent direct and return passages for conductingsaid fluid to and from said first named means.

8. In combination, an internal combustion engine, a carburetor forsupplying fuel to said engine, a pump, a self-contained closedcirculating system comprising a plurality of independent passages forcontaining a liquid and vapor thereof and means for converting theliquid in said circulating system into a vaporized fluid for operatingsaid pump for supplying fuel to said carburetor, said system having aplurality of conduits for conducting fluid to and from said pump.

CHARLES LAWRENCE STOKES.

